Deep links are always very essential to support your SEO strategy and it is useful to optimize your site in order to get well ranked especially if you join SEO Contest such as Stop Dreaming Start Action. Do you really know what deep links are? It is a link from a page of website or blog that links directly to an inner page of another website.
It is a little bit different between deep links and backlinks as backlinks just a link from the website while deep links are a links point to a specific piece of information or relevant topic.
I am sure that deep links are really important because while getting links to your homepage certainly has it's place in SEO, it doesn't even come close to the results you get from a deep link
People who arrived at a website through homepage as stated by Nielson is about 40% while 60% arrived from deep links in 2004.
People who visit web from homepage decreased to 25% and others via keywords and arrived at the information directly they are looking for Unfortunately, most people like instant process, so they like to find information via keywords. Especially when it comes to technology like the Internet That's why search engines come to us to fulfill this need, and they are partially responsible for it by making algorithms to decide what sites or blog are really suitable to rank no.1 in google.
This is the reason why you need deep links to make your blog or site well ranked.
Having an optimized internal linking structure for your site is important as well and it helps the Search Engine robots drill down through your site and create a list of pages for inclusion in their databases, but I think it not a guarantee that you will get the first page in search engines. It is also very important to arrange and make internal linking structure for your site to help search engines crawl your sites for being stored and calculated. You know that internal links are made by webmaster , so Search Engines do not believe such that kind of links. Blame the thousands of unscrupulous webmasters that that were not responsible of the SE's using sneaky black hat methods
On the other hands, deep link from another websites is really a vote for your site that google really like. The search engine robots will follow these links, and again using very smart algorithms and technology, will extract data and determine the value of the page, links and thus inclusion in future search results